The k2p blog

………. years with positive SSN anomalies featuring high peripheral month sunspot numbers but low in-season numbers have, on average, significantly more (79%) US hurricanes. The SSN anomaly was shown to be statistically significant in models for US hurricanes and US major hurricanes after accounting for the other climate variables.

Abstract:

The relationship between US hurricanes and solar activity is investigated empirically. First, a relationship between the probability of a US hurricane and the solar cycle is shown conditional on sea surface temperatures (SST). For years of above normal SST, the probability of three or more US hurricanes decreases from 40 to 20% as sunspot numbers (SSN) increase from lower to upper quartile amounts. Second, since SST is in phase with the 11-year total solar irradiance cycle but upper-air temperature is in phase with ultraviolet radiation changes on the monthly time scale, an anomaly index of SSN is constructed. The index is significantly correlated with US hurricanes and major US hurricanes over the period 1866-2008. The chances of at least one hurricane affecting the United States in the lowest and highest SSN anomaly seasons are 68 and 91%, respectively. A similar relationship is noted using hurricane records spanning the period 1749-1850, providing independent corroborating evidence linking solar variability to the probability of a US hurricane.

The evidence for a sun–hurricane relationship was further bolstered by showing that a similar relationship between the SSN anomaly and US hurricanes (years of high SSN anomaly have more US hurricanes) is detectable in an archive of Atlantic hurricanes dating back to 1749. ……….